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IN THIS ISSUE:

* It's Baaaaack!
* Technical Update
* RMRL Hamfest
* Holiday Dinner Announcement
* Choose Your 2M Frequency Wisely
* RMRL Club Information

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IT'S BAAAAACK!

QRZ is back after taking the spring quarter off. The officers and
committee members have been doing their usual excellent work and all
club repeaters continue to hum along. So there just hasn't been much
to write about! Every ham club should have this "problem"!

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TECHNICAL UPDATE
by Glenn, WN0EHE

Last summer several of the club's repeater sites experienced damage due
to lightning. This year we have been much more fortunate. In July an
emergency trip to Guy Hill was made by N0MHU and WN0EHE because the
224.000 and 449.750 repeaters were down, and the 145.220 repeater was
on battery power. Lightning damage was found. The main fuse was blown
in the power panel that feeds power to the building. The powerline
protection equipment was intact and all three repeaters were returned to
service. On Tuesday August 27th there was another lightning storm on
Guy Hill and the 224.000 and 449.750 repeaters went down again. The
145.220 repeater ran for a few days on battery power. The following
weekend N0MHU and WN0EHE went to Guy Hill to repair damage to the
lightning protection components on the AC powerline. The radio equipment
was returned to the air without damage.

In July during one of the RMRL Monday night nets, the 146.940 and 449.450
repeaters went down. After about 5 minutes the repeaters came back up.
It was determined that the power supply which runs both repeaters was
overheating and shutting down. The following weekend WU0N, N0MHU, and
WN0EHE went to Squaw Mountain and found that the cooling fan in the power
supply was not operational. A new fan was installed and no further
problem with overheating has been experienced.

Because of the situation with the Squaw Mountain power supply and due to
the high usage of the 145.340 IRLP repeater, N0MHU and WN0EHE went to the
34 site the following weekend to install an additional fan in the power
supply. Earlier in the summer WY0X and WN0EHE went to the 34 site to try
to locate the source of the video noise that had been bothering the repeater.
The noise was not present that day (of course), and has been gone most of
the summer. It does return intermittently. If you hear the noise and the
repeater is connected to the IRLP system, please drop the link.

Recently we have noticed that the link receiver at the 449.825 Broomfield
repeater is experiencing intermittent loss of sensitivity. We are planning
a repair trip in the near future.

The rest of the RMRL equipment has continued to run without problems or
failures.

Thanks to everyone that has helped to keep the RMRL repeaters, the IRLP
node, and the ELT monitors on the air, including WY0X, N0PSR, WB5YOE,
K0CO, WB4ETT, N0TI, N0MQJ, WU0N, WT0C, and N0URK.

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RMRL HAMFEST

Hope to see you at upcoming RMRL hamfest! Support your club by coming
out and having a great time! Postcards with the details of the event were
sent out previously, but here's a recap:

When: Saturday, October 19th, 2001, 8 AM - 2 PM
Where: Jefferson County Fairgrounds, 15200 W. 6th Avenue, Golden, CO
(directions: Indiana exit from 6th Avenue)
Talk-in: 144.62/145.22 MHz
Admission: $5/person (12 and under free)
Tables: $10 in advance and at the door

This year we have FOUR GREAT GRAND PRIZES:

1st Prize: Yaesu FT-1500M 2 Meter Mobile Transceiver
2nd Prize: Yaesu VX-150 2 Meter Handheld Transceiver
3rd Prize: Icom IC-Q7A Dual Band Handheld Transceiver
4th Prize: Daiwa CN-101 Cross Needle SWR/Wattmeter

Like last year, the club is not mailing raffle tickets to members, so the only
way you can win one of these prizes is to ATTEND THE HAMFEST! The grand
prize drawing will be held at 1 PM. Additionally, door prizes will be
given away throughout the day.

Another reason to attend is to take advantage of the usual RMRL membership
special that will be offered. The regular RMRL family membership fee is $20
for twelve months. However, current members can renew or extend their family
memberships and receive fifteen months for $20. New members will also receive
fifteen months for $20. There is no limit to the number of fifteen month membership
periods which can be purchased. There are two catches, however. First, you must
attend the Hamfest and come by the RMRL club table to sign up (the membership special
is not available by mail). Second, the special does not apply to youth individual
memberships.

Other features include an ARRL forum (at 9 AM), VE testing (at 10 AM),
and refreshments provided by Boy Scout Troop 3 of Aurora.

Thanks to our Hamfest chairman, Ron, N0MQJ, for all his hard work
organizing this event. Ron can use lots of volunteers on Hamfest day,
so please contact him at 303-985-8692 or n0mqj@attbi.com if you can help
out. Volunteers get free admission to the Hamfest and a free lunch!

For additional Hamfest information, give Ron a call or visit the club
web site at http://rmrl.hamradios.com.

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HOLIDAY DINNER ANNOUNCEMENT

Summer isn't even over yet, but the holidays will be here before we know
it. Mark your calendars now for the annual RMRL holiday dinner! It
will be held on Wednesday, December 11 starting at 6:30 PM. The location
is the Country Buffet restaurant, 301 West Girard Avenue in Englewood.
This is the same place we have met the past several years. The cost for
all you can eat is $8.89 (plus tax) for adults, $8.19 (plus tax) for
seniors, and 55 cents (plus tax) per year of age for kids. We hope to
see you there!

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CHOOSE YOUR 2M FREQUENCY WISELY
By Bob Witte, K0NR

You've just purchased your first 2M FM transceiver and have been chatting
with both old and new friends around town on the 2M band. You and your
buddies decide to find an out of the way frequency to hang out on. After
tuning around, you find a nice, quiet frequency that no one seems to using
and start operating there. Nothing to worry about, right? Not so fast,
there are a few more things to consider when selecting a frequency on the
2M band. Let's take a look at the key issues.

FCC Rules

The first thing we need to know are the frequencies that the FCC has
authorized for our particular license class. For the HF bands, the
frequency privileges depend greatly on the license class of the operator.
Above 50 MHz, the frequency allocations are the same for Technician
licenses and higher. In particular, the 2M band extends from 144 MHz to
148 MHz. The FCC Rules say that any mode (FM, AM, SSB, CW, etc.) can be
used on the band from 144.100 M to 148.000 MHz. The FCC has restricted
144.0 to 144.100 MHz to CW operation only.

Band Plans

Knowing the FCC frequency authorizations is a good start but we need to
check a bit further. Amateur radio operators use a variety of modulation
techniques to carry on communications. Often, these modulation techniques
are incompatible since a signal of one type can't be received by a radio
set to another modulation type. For example, an SSB signal can't be
received on an FM receiver (and vice versa). We need to use our authorized
frequencies wisely by sharing the band with other users and avoiding
unnecessary interference. Thus, it makes sense to have a band plan that
divides the band up into segments for each type of operation.

2M Band Plan

As shown in the table, the 2M amateur band plan supports a wide variety of
radio operation. Large portions of the band are dedicated to FM operation,
consistent with the popularity of the FM mode. There are portions of the
band designated for repeater outputs (which is the frequency that we tune
to receive the repeater) and repeater inputs (which is the frequency we
transmit on to use the repeater). Notice that these segments are
positioned 600 kHz apart consistent with the standard 2M repeater offset.
There are also frequencies designated for FM simplex.

On the low end of the band, we see segments for some of the more exotic
modes. At the very bottom is the CW portion, which includes
Earth-Moon-Earth (EME) operation. EME operators communicate by bouncing
their signals off the moon.

2M Band Plan (as approved by the ARRL VHF-UHF Advisory Committee,
simplified by K0NR to reflect usage in Colorado):

144.000-144.100: CW
144.100-144.275: Single-sideband (SSB Calling Frequency = 144.200)
144.275-144.300: Propagation Beacons
144.300-144.500: OSCAR (satellite)
144.500-144.900: FM Repeater Inputs
144.900-145.100: Packet Radio
145.100-145.490: FM Repeater Outputs
145.500-145.800: Misc. and experimental modes
145.800-146.000: OSCAR (satellite)
146.010-146.370: FM Repeater Inputs
146.400-146.580: FM Simplex
146.610-147.390: FM Repeater Outputs
147.420-147.570: FM Simplex
147.600-147.990: FM Repeater Inputs

Note: The FM channel spacing in Colorado is 15 kHz (repeaters and
simplex).

Further up the band, we see segments for SSB operation and beacon
operation. SSB is the preferred voice mode for so-called "weak signal"
operators. The mode is more efficient than FM when signals are weak, so it
is the way to go when you are trying to push the limits of 2M DX. Beacons
are transmitters that are always on, transmitting a short CW message to as
a propagation indicator for distant stations. We often think of 2 Meters
as a local coverage band but when conditions are right, contacts can be
made with stations over a thousand miles away. Of course, conditions are
not always right so having a beacon on the other end of the desired
communication path lets you know how propagation is in that direction.

Radio amateurs also use 2 meters for OSCAR satellite operation, sending
signals to a satellite (uplink) or receiving signals from the satellite
(downlink). The OSCAR segments don't specify a particular modulation type
since CW, SSB and FM are all used for OSCAR operation. Because of their
elevation above the earth, satellites can hear signals from all over the
US simultaneously, so they are very susceptible to interference.

Most of this non-FM operation can be easily interfered with by signals
from other users. EME signals, for example, are usually quite weak since
the signal has to make the round trip from the earth to the moon and back.
If a local FM operator fires up in the EME portion of the band, an EME
signal that can't be heard by an FM receiver can be wiped out by the FM
signal. Similarly, an operator chatting across town on 2M could interfere
with a satellite hundreds of miles away and not know it. This is
particularly a problem with FM receivers, which won't even notice low
level CW and SSB signals.

FM Operating

The most common 2M rigs are basic FM mobile or handheld transceivers.
These radios usually tune the entire 2M band from 144 MHz to 148 MHz in 5
kHz steps. The band plan indicates the proper range of frequencies for FM
operation but there is more to the story. FM operation is "channelized",
meaning that specific 2M FM frequencies are identified by the band plan.
The use of channels is especially important for repeaters, since they
don't easily move around in frequency and are coordinated to minimize
interference. The idea is to have all stations use frequencies that are
spaced just far enough apart to accommodate the signal without interfering
with the adjacent channels.

You might think that the spacing between channels would be 5 kHz, which is
the tuning step of most FM radios. This doesn't work because an FM signal
occupies a bandwidth that more than 5 kHz wide. Even though we talk about
a signal being on a specific frequency, the signal actually spills out on
either side of the frequency by about 8 kHz. This means that a typical FM
signal is about 16 kHz wide. You may recall that amateur 2M FM uses 5 kHz
frequency deviation. So doesn't this mean the bandwidth is 10 kHz? No, it
doesn't work quite that way and the signal is actually wider than 10 kHz.
I might be able to show the math behind this but it makes my head hurt.
Perhaps in some future article.

The channel spacing needs to be at least as wide as the bandwidth of the
signal, which allows room for each signal without interfering with the
adjacent channel. In Colorado, the channel spacing is 15 kHz, which is a
bit tight for our 16 kHz-wide signal. In other parts of the country, a 20
kHz spacing has been adopted to provide for more separation between
channels. Obviously, you get more channels on the band with 15 kHz spacing
than with 20 kHz, but you have to put up with more adjacent channel
problems.

When using a repeater, you just need to dial in the published repeater
frequency and set the transmit offset, either + 600 kHz or - 600 kHz. Most
modern 2M radios automatically take care of setting the proper offset
(based on the band plan). If you need to set the offset manually, the rule
is very simple. If a repeater's output frequency is in the 147 MHz range,
it uses a + 600 kHz offset. Otherwise, it requires a - 600 kHz offset.
For simplex operation, the standard simplex frequencies listed in the
table below should be used. These simplex frequencies are grouped in the
146 MHz and 147 MHz range as listed in the table below. The National
Simplex Frequency (also referred to as the calling frequency) is 146.52
MHz.

2M FM Simplex Frequencies - Colorado Band Plan:

146 MHz Range: 146.400, 146.415, 146.430, 146.445, 146.460, 146.475,
146.490, 146.505, 146.520, 146.535, 146.550, 146.565, 146.580,
146.595

147 MHz Range: 147.405, 147.420, 147.435, 147.450, 147.465, 147.480,
147.495,147.510, 147.525, 147.540, 147.555, 147.570, 147.585

The FCC View on Band Plans

Sometimes I hear radio amateurs say, "Band plans are voluntary so I don't
need to pay any attention to them. I can do whatever I want as long as I
don't break the FCC rules." Unfortunately, such an attitude does not
promote efficient use and sharing of the amateur bands. Imagine the chaos
on the ham bands if everyone took this approach. It also may be a
violation of FCC rules.

On Oct 18, 2000, in a ruling concerning a repeater operator's failure to
conform to the prevailing band plan, FCC Special Counsel for Amateur Radio
Enforcement, Riley Hollingsworth commented on the issue. He said "Band
plans minimize the necessity for Commission intervention in Amateur
operations and the use of Commission resources to resolve amateur
interference problems. When such plans are not followed and harmful
interference results, we expect very substantial justification to be
provided, and we expect that justification to be consistent with Section
97.101."

Section 97.101 is the part of the FCC rules that says (among other
things) that (1) in all respects not specifically covered by FCC Rules
each amateur station must be operated in accordance with good engineering
and good amateur practice; and (2) each station licensee and each control
operator must cooperate in selecting transmitting channels and in making
the most effective use of the amateur service frequencies.

The FCC has clearly stated that they expect hams to share the bands by
following accepted band plans. More importantly, this is the right thing
to do for the benefit of the amateur radio service.

Summary

The fine points of the band plan can be a bit confusing. However, a few
simple guidelines can help, especially if you are operating only FM.
FM voice simplex and repeater operation should occur only above
145.100 MHz (and only in the OSCAR subband if you are working an FM
satellite).

When operating through a repeater, make sure you are tuned to the
published repeater frequency with the right transmit offset.
When operating simplex, use a simplex frequency designated by the
band plan.

We've only covered the 2 meter band in this article. If you are operating on
other bands, be sure to check the appropriate band plan before transmitting.
Note that this article is written for amateur radio operation in Colorado.
Other locations may have different band plans for the 2M band.

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ROCKY MOUNTAIN RADIO LEAGUE, INC. - W0WYX
An ARRL Special Service Club
Post Office Box 3821
Littleton, CO 80161-3821

E-mail: rmrl@juno.com
Web: http://rmrl.hamradios.com

Weekly On-the-Air Meeting and Net:
Monday Nights, 8:30 PM local, 146.940, 449.450, and 449.825 MHz

Officers:
---------

President - Glenn Cascino, WN0EHE
Vice President/Secretary - Ron Rose, N0MQJ
Treasurer - Joe Dickinson, WT0C

Committee Members:
------------------

Hamfest - Ron Rose, N0MQJ
Membership - Mike Weaver, KA6YFB
Monday Night Net - Dave Geyer, WU0N
QRZ Newsletter - Joe Dickinson, WT0C
Newsline Report - Bruce Minerly, KB0PHD
Web Page - Ron Rose, N0MQJ
IRLP - Kent Roberts, N0PSR
Technical - Ed Boyer, N0MHU; Glenn Cascino, WN0EHE;
Jack Dougherty, K0CO; Bob Ragain, WB4ETT;
Bob Schellhorn, N0TI; Richard Shaw, WB5YOE;
Jim Ungry, W0LGF

Repeaters
---------

145.220 MHz, NW of Golden, CO
145.340 MHz, near Evergreen, CO
145.430 MHz, SW of Boulder, CO
146.940 MHz, near Idaho Springs, CO
224.000 MHz, NW of Golden, CO
449.125 MHz, W of Sedalia, CO
449.450 MHz, near Idaho Springs, CO
449.750 MHz, NW of Golden, CO
449.825 MHz, near Broomfield, CO
449.875 MHz, SW of Boulder, CO

Trustees
--------

Glenn Cascino, WN0EHE (145.220)
Joe Dickinson, WT0C (145.340)
Ron Rose, N0MQJ (145.430)
Dave Geyer, WU0N (146.940, 449.825, and club license)
Warren Gretz, N0FVG (449.125 MHz)
Ed Boyer, N0MHU (224.000 and 449.875)
Bob Ragain, WB4ETT (449.450)
Bob Schellhorn, N0TI (449.750)